#include<stdio.h>
int hour, minute, second;
void Update()
{
	second++;
	if (second == 60)
	{
		second = 0;
		minute++;
	}
	if (minute == 60)
	{
		minute = 0;
		hour++;
	}
	if (hour == 24)
	{
		hour = 0;
	}
}
void Display()
{
	printf("%d:%d:%d\n", hour, minute, second);
}
void Delay()
{
	int t;
	for (t = 0; t < 100000000; t++);
}
int main(void)
{
	int i;
	hour = minute = second = 0;
	for (i = 0; i < 1000000; i++)
	{
		Update();
		Display();
		Delay();
	}
	return 0;
}